diff options
| author | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2018-11-23 07:13:04 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2018-11-23 17:31:10 +0300 |
| commit | 90e8ac5c9d446124a5b43a6f135bf67e060c0c9d (patch) | |
| tree | e2d794e24286fb5df93e98c3ae1772ed662d57d0 /sound/firewire/tascam/tascam-hwdep.c | |
| parent | 33b2e1442aeaacabb4e29f8adb31469e87599b16 (diff) | |
| download | linux-90e8ac5c9d446124a5b43a6f135bf67e060c0c9d.tar.xz | |
ALSA: firewire-tascam: add new hwdep ioctl command to get state image
In a previous commit, ALSA firewire-tascam driver stores state image
from tx isochronous packets. This image includes states of knob, fader,
button of control surface, level of gain/volume of each physical
inputs/outputs, and so on. It's useful for userspace applications to
read whole of the image.
This commit adds a unique ioctl command for ALSA hwdep interface for the
purpose. For actual meaning of each bits in this image, please refer to
discussion in alsa-devel[1].
[1] http://mailman.alsa-project.org/pipermail/alsa-devel/2018-October/140785.html
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/firewire/tascam/tascam-hwdep.c')
| -rw-r--r-- | sound/firewire/tascam/tascam-hwdep.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sound/firewire/tascam/tascam-hwdep.c b/sound/firewire/tascam/tascam-hwdep.c index 4e4c1e9020e8..a80397116c48 100644 --- a/sound/firewire/tascam/tascam-hwdep.c +++ b/sound/firewire/tascam/tascam-hwdep.c @@ -123,6 +123,14 @@ static int hwdep_unlock(struct snd_tscm *tscm) return err; } +static int tscm_hwdep_state(struct snd_tscm *tscm, void __user *arg) +{ + if (copy_to_user(arg, tscm->state, sizeof(tscm->state))) + return -EFAULT; + + return 0; +} + static int hwdep_release(struct snd_hwdep *hwdep, struct file *file) { struct snd_tscm *tscm = hwdep->private_data; @@ -147,6 +155,8 @@ static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file, return hwdep_lock(tscm); case SNDRV_FIREWIRE_IOCTL_UNLOCK: return hwdep_unlock(tscm); + case SNDRV_FIREWIRE_IOCTL_TASCAM_STATE: + return tscm_hwdep_state(tscm, (void __user *)arg); default: return -ENOIOCTLCMD; } |